Caulking tubes (e.g., polyurethane or cardboard tube containers) are widely used for packaging of various materials such as sealants, adhesives, and other caulking compositions. These materials are normally paste or gel materials which harden when exposed to the environment.
Such tubes include a tapered dispensing nozzle at their leading end. The nozzle can be cut off at a desired location to enable the contents of the tube to be dispensed by a caulking gun which advances a plunger or disk through the tube.
Oftentimes the entire contents of a caulking tube are not used at one time or on one jobsite. As a result, the composition in the tube will begin to dry out or cure. The longer the opened tube is stored before it is used again, the more of the composition that will undesirably cure. Because the compositions sold in caulking tubes are often very expensive, it can be quite costly when the composition cures in the tube and is therefore wasted.
Sometimes it is possible to dig out cured composition from the open end of the nozzle of the tube if the tube hasn't been stored too long after being opened. However, often it is not possible to do this because the composition has cured too deep. Sometimes it is possible to cut an additional length off the nozzle to allow access to uncured composition in the tube, but this procedure leaves too large an opening in the nozzle for useful dispensing of the composition.
Although it has been proposed to put a cap member over the open end of a caulking tube nozzle, this has not been entirely successful because some air remains in the nozzle or leaks past the cap. Thus, the composition can still become cured or hardened during storage, at least at the outer end of the nozzle.
A tapered dispensing tip has also been proposed for fitting over a caulking tube nozzle. However, the tip does not seal the end of the nozzle after the composition has been dispensed from the tube.
Although various types of spouts, caps and nozzles have been used on cans, tubes and bottles, none of such devices are suitable or practical for use on caulking tubes in a manner such that (1) the composition in the tube can be easily and readily dispensed, (2) the tube can be effectively sealed to prevent the composition in the tube and nozzle from hardening prematurely during shortage, and (3) the nozzle can be re-used on a variety of caulking tubes without modification and without loss of effectiveness.
There has not heretofore been proposed a technique or system for sealing the open nozzle of a caulking tube having the advantages provided by the present invention.